Toe iron for safety ski bindings

ABSTRACT

A baseplate carries a vertical pivot pin, on which a pivoted member is rotatably mounted which carries a soleholder, which is pivoted to the pivoted member on an axis which is parallel to the pivot pin on the baseplate. The soleholder is normally held against rotation by a detent device, which comprises a first member that is movable relative to a second member of the detent device to release the latter. The first member of the detent device is under the influence of the pivoted member in such a manner that the soleholder will be released when said member has performed a predetermined pivotal movement from its normal position.

United States Patent [72] Inventor Ludwig Axthammer Garmisch-Partenkirchen, Germany [21] Appl. No. 761,036 [22] Filed Sept. 20, 1968 [45] Patented Oct. 5, 1971 [73] Assignee I-Iannes Marker Garmisch-Partenkirchen, Germany [32] Priority Sept. 22, 1967 1 1 Germany [31] P 15 78 857.5

[54] TOE IRON FOR SAFETY SKI BINDINGS 11 Claims, 5 Drawing Figs.

52 0.5. Ci ..280/ll.35T [51] Int. Cl A63c 9/085 [50] Field of Search 280/11.35 HA, 11.35 H, 11.35

[56] References Cited UNITED STATES PATENTS 3,037,785 6/1962 DePlace 280/1 1.35 (HA) l a 6 i Q 5 l w Primary Examiner-Benjamin Hersh Assistant Examiner-Milton L. Smith Attorney-He, Gipple & Jacobson ABSTRACT: A baseplate carries a vertical pivot pin, on which a pivoted member is rotatably mounted which carries a soleholder, which is pivoted to the pivoted member on an axis which is parallel to the pivot pin on the baseplate. The soleholder is normally held against rotation by a detent device, which comprises a first member that is movable relative to a second member of the detent device to release the latter. The first member of the detent device is under the influence of the pivoted member in such a manner that the soleholder will be released when said member has performed a predetermined pivotal movement from its normal position.

PATENIEDUBT 5mm 3510.649"

SHEET 2 BF 2 Fig.5

4 5 22 1 i r --a K////f 76 Fig. 4

Firm/5y:

TOE IRON FOR SAFETY SKI BINDINGS The present invention relates to a toe holder which is intended for use in safety ski bindings and which has a baseplate carrying a vertical pivot pin, on which a pivoted member is rotatably mounted which carries a soleholder, which is pivoted to the pivoted member on an axis which is parallel to the pivot pin on the baseplate, the soleholder being normally held against rotation by a detent device.

In this known toe iron, the-detent resistance is adjustable so that the force required for a release, the so-called release hardness, is variable. In the use of this known toe iron, a contact pressure is required between the skiing boot and the soleholder and the value of said contact pressure and the detent resistance determine the extent of the elastic zone which must be traversed before the detent is released and in which forces are resiliently taken up which act transverse to the ski and which are harmless to the leg of the skier. With different release hardnesses, the extent of the elastic zone differs too. A large elastic zone will be obtained if the detent resistance is high and the pressure applied by the skiing boot is high too. The elastic zone is small if both the detent resistance and the contact pressure applied by the skiing boot are small.

It is an object of the present invention to improve a toe iron of the type previously described so that the elastic zone has a predetermined, sufficiently large extent regardless of the release hardness.

In a toe iron which is intended for use in safety ski bindings and which has a baseplate carrying a vertical pivot pin, on which a pivoted member is rotatably mounted which carries a soleholder, which is pivoted to the pivoted member on an axis which is parallel to the pivot pin on the baseplate, the soleholder being normally held against rotation by a detent device, the above-mentioned object is accomplished according to the invention in that the detent device comprises a first member which is movable relative to a second member of the detent device to release the latter. The first member is under the influence of the pivoted member in such a manner that the soleholder will be released when said member has performed a predetermined pivotal movement from its normal position. In such an arrangement,'the release hardness is no longer dependent on the detent resistance and a simple, nonadjustable detent device can be used, which no longer depends on a frictional connection, as before, but on a positive connection.

When the invention is applied to a toe iron in which the pivoted member is rotatable against spring force and is capable of a limited upward displacement in dependence on said rotation, it has been found desirable to provide an arrangement in which the detent device is releasable by the upward movement of the pivoted member.

For reasons of manufacturing technology, the detent element of the detent device is coaxial to the pivot pin that is fixed to the ski. The detent element is held on said pivot pin and the soleholder is provided with the detent socket. The free end of the pivot pin may serve as a detent element. Altematively, the detent element may consist of a pin, which is longitudinally slidably held in the pivot pin and with its free end protrudes from the pivot pin and is adapted to be forced into the pivot pin against a returning force.

To enable an engagement of the detent device when it has been released, oblique cam surfaces are provided on the soleholder on both sides of the detent socket.

If the toe holder comprises a helical compression spring which opposes the movement of the pivoted member and is mounted on the pivot pin that is fixed to the ski, a feature of the invention may reside in that the helical compression spring bearing at one end on the pivoted member bears at its other end on a nut, which is longitudinally displaceably and nonrotatably held in the pivoted member and screwed on' the pivot pin, which for this purpose is provided with screw threads. In this case, a scale is provided at least on one longitudinal side of the slot and the nut may carry a stud, which enters a vertical slot in the pivoted member to hold the nut against rotation. It will then be suitable to provide a scale at Another feature of the present invention can be used to special advantage in a toe iron of the kind previously described and resides in that the soleholder comprises a pedal for engaging the underside of the forward end portion of the sole of the skiing boot. The action of a force having a direction thatis transverse to the ski results normally in the occurrence of dangerous frictional forces between the skiing boot and the ski, which forces oppose a movement of the skiing boot in the releasing sense and cannot be exactly predicted so that they cannot be taken into account when the binding is being adjusted. The occurrence of such frictional forces will be virtually avoided if the last-mentioned feature of the invention is adopted.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which FIG. 1 is a central longitudinal sectional view showing a first embodiment of a toe iron according to the invention.

FIG. 2 is a top plan view of FIG. 1.

FIG. 3 is a top plan view similar to FIG. 2 but shows the toe iron in the released position.

FIG. 4 is a central longitudinal sectional view showing a toe iron in an embodiment which is only slightly modified from the first.

MG. 5 is a central longitudinal sectional view showing a toe holder in a third embodiment.

In a toe iron shown in FIGS. 1 to 3,. consisting of a so-called double-pivot toe iron, the baseplate 1 has two screw holes 2 for use in a screw-connecting the toe iron to a ski. A vertical pivot pin 3 is riveted into the baseplate and a pivoted member 4 is rotatably mounted on the pivot pin 3. The pivot pin also carries a helical compression spring 5, which acts at one end on the pivoted member and bears at its other end on a collar of the pivot pin. The pivot pin 3 is provided at its lower end with two oblique surfaces 6 and 7, which in the normal position of the pivoted member are in mating engagement with the oblique surfaces of the pivoted member 4, which is urged against the oblique surfaces 6 and 7 by the helical compression spring 5. During the movement of the pivoted member about the pivot pin 3, the oblique surfaces 6 and 7 form camming surfaces for the pivoted member so that the latter is moved axially upwardly against the force of the helical compression spring.

A soleholder 9 is secured by a pivot pin 8 to the pivoted member 4. The two arms l0 and 11 of the soleholder engage the forward end portion of the sole on top and embrace the toe portion of the boot. The vertical portion of the soleholder bears on the toe portion of the boot and comprises in known manner two teeth 12 and 13, which engage corresponding recesses in the toe portion of the sole to ensure a positive transmission of motion under the action of lateral forces.

That portion of the soleholder 9 which normally overlies the pivoted member 4 is formed with a blind hole 14, which forms part of a detent device. The detent element of thedetent device is constituted by the stepped free end portion 15 of the pivot pin 3.

By this device, the pivoted member 4 and the soleholder 9 are normally interlocked. This interlock can be released in that the pivoted member 4 is rotated to a predetermined extent about the pivot pin 3 because this rotation positively results in an upward axial displacement of the pivoted member 4 against the force of the helical compression spring 5.

The oblique surfaces 6 and 7 of the pivot pin 3 may be designed so that the axial displacement of the pivoted member and an increase of the stress of the helical compression spring 5 take place only until the release position is reached whereas virtually no effort is required to continue the rotation of the pivoted member about the pivot pin 3 If a force in a direction that is oblique to the longitudinal direction of the ski acts on the soleholder 9 via a tooth 12 or 13, that force will tend to turn the soleholder and with it the pivoted member 4 about the pivot pin 3 because the parts 4 and 9 are interlocked against the force of the helical compression spring 5 as the member 4 runs up on the oblique surfaces 6 and 7 during its pivotal movement. When the force acting on the soleholder is reduced, the spring urges the pivoted member and with it the soleholder back to its initial position. When a larger force, which is dangerous to the leg of the skier, acts on the soleholder 9, the spring is compressed to such an extent that the soleholder 9 clears the detent element formed by the end portion of the pivot pin 3. The soleholder 9 is now unlocked and can move freely about the pivot pin 8. The toe holder is now collapsed in the manner known from previous two-pivot toe irons and enables a virtually sudden release of the sole of the boot. The unlocked condition of the toe iron is shown in FIG. 3.

To return the toe iron to a position ready for skiing after a safety release operation, the soleholder 9 must first be pivotally moved until the hole 14 is coaxial to the pivot pin 3. The pivoted member 4 must then be pivotally moved back to the end of the elastic zone and from this position moves automatically back to its normal position by a relaxation of the helical compression spring 5. During the riding of the pivoted member 4 on the oblique surfaces 6 and 7, the end portion 15 of the pivot pin 3 automatically enters the hole 14. The pivoted member 4 is sufficiently strongly locked in its intermediate position under the initial stress of the helical compression spring 5.

In the embodiment just described, the toe iron is virtually independent of the pressure applied by the boot. Compared to the known toe iron which has been described first, the distance from the teeth 12 and 13 to the pivot pin 3 is relatively large so that the pivotal movement within the elastic zone results only in an insignificant displacement of the skiing boot in the longitudinal direction of the ski and only in a slight increase of the retaining force that is produced by a heel holder.

During a pivotal movement of the pivoted member 4 back into its normal position, a renewed pivotal movement of the member 4 to the release position should not be required before the soleholder 9 has been correctly positioned. To this end, oblique cam surfaces 16 and 17 are provided on the soleholder on both sides of the hole 14. These surfaces are indicated by dash-dot lines in FIGS. 2 and 3. When the pivoted member 4 is in normal position, i.e., when the end portion 15 of the pivot pin 3 protrudes upwardly above the pivoted member, the soleholder can still be pivotally moved to its normal position. In this case, however, the pivoted member 4 must be moved upwardly against the force of the helical compression spring 5 to an extent which corresponds to the length of the stepped end portion 15.

FIG. 4 shows a toe iron which differs from the previously described design in that the force of the helical compression spring 5 need not be overcome for a pivotal movement of the soleholder member 9 to its normal position when the pivoted member 4 is already in its central position. To this end, the pivot pin 20 does not have a stepped end portion but carries a plunger 21, which is disposed in an axial bore of the pivot pin and with its free end normally protrudes from the pivot pin.

The plunger can be depressed into the pivot pin against the force of a relatively weak restoring spring 22. In other respects, the toe iron is exactly the same in design and mode of operation as that of FIGS. 1 to 3. For this reason, the same reference characters are used for like parts.

FIG. 5 shows a toe iron which embodies the invention and enables an adjustment of the release hardness. The same reference characters are again used for like parts. The pivot pin which is riveted into the baseplate has in this case at its free end no collar but is provided with screw threads in threaded engagement with a nut 26, on which the helical compression spring 5 can hear. The nut is longitudinally slidably and nonrotatably held in the pivoted member 27. It is held against rotation by a stud 28, which enters a vertical slot 29 in the pivoted member. This pin serves at the same time as an indicator of the release hardness. To this end, a scale, not shown, is provided on one longitudinal side of the slot.

The nut 26 is shown in the position which corresponds to the smallest release hardness. The nut 26 can be screwed further onto the pivot pin 25 to increase the stress of the helical compression spring 5 in that the pivoted member 27 is rotated together with the soleholder 9. This will not result in a change of the elastic zone or the release point because the latter is determined by the design of the oblique surfaces 6 and 7. The hardness can easily be adjusted without need for a tool because the soleholder 9 constitutes a long lever arm.

It has already been mentioned with reference to FIGS. 1 to 3 that the distance of the teeth 12 and 13 from the pivot pin 3, 20, or 25, is much larger than in the known toe irons which are pivotally movable about a pivot pin. For this reason, a soleholder which embraces the toe portion of the boot may be used without a risk that the toe portion of the boot may be squeezed out or clamped.

When it is desirable or necessary to enable an adjustment of the arms 10 and 11 of the soleholder 9 to skiing boot soles differing in thickness, the soleholder can readily be designed so as to meet this requirement.

According to another feature of the present invention the soleholder 9 comprises a pedal 18, which engages the underside of the forward end portion of the skiing boot. As a result, this sole end portion will not contact the surface of the ski so that the dangerous frictional forces are avoided, which otherwise occur between the skiing boot and the ski as a result of a force that is transverse to the ski. This result is of great significance of the safety function of the device because the frictional forces may be considerable.

The use of a pedal is not restricted to the embodiments which have been described by way of example but may also be applied to other toe irons.

I claim:

1. A toe iron for safety ski bindings comprising a baseplate, a vertical pivot pin secured to said baseplate, a spring carried by said vertical pivot pin, a swivel member rotatably mounted on said vertical pivot pin, a soleholder member rotatably mounted to said swivel member around an axis lying parallel to said vertical pivot pin, said soleholder member being normally held against rotation relative to said swivel member by an antirotation lock, said antirotation lock comprising a locking pin which extends in locked position through a horizontal division between said swivel member and said soleholder member, said soleholder member being unlocked from the locking pin by swinging the swivel member through a predetermined angle out of a central position by relative displacement of the swivel member in opposition to the force of said pivot pin spring.

2. A toe iron according to claim 1, wherein said antirotation lock comprises two parts, one part being mounted coaxially on said vertical pivot pin and the other part being a socket provided in said soleholder.

3. A toe iron according to claim 2, wherein the free end portion of said pivot pin defines said one part of said antirotation lock.

4. A toe iron according to claim 2, wherein said one part of said antirotation lock comprises a plunger slidably held axially in said pivot pin with the free end portion of said plunger protruding from said pivot pin and restoring means biasing said plunger outwardly.

5. A toe iron according to claim 2, wherein said soleholder defines an oblique cam surface on each side of said socket to guide said one part of said antirotation lock.

6. A toe iron according to claim 1, including adjusting means for adjusting the force of said spring.

7. A toe iron according to claim 6, wherein said adjusting means comprises, a nut contained within said swivel member and threadably engaged with said pivot pin.

8. A toe iron according to claim 7, wherein a stud coacts with said nut and said pivot pin to prevent rotation of said nut relative to said pivot pin.

9. A toe iron according to claim 8, wherein said swivel member defines a vertical slot through which said stud pro jects, and a release hardness scale is provided on one side of said slot so that said stud constitutes an indicator of the release hardness.

are fastened to the skis for the swivel member to provide for the relative displacement of said locking pin between said swivel member and said soleholder member. 

1. A toe iron for safety ski bindings comprising a baseplate, a vertical pivot pin secured to said baseplate, a spring carried by said vertical pivot pin, a swivel member rotatably mounted on said vertical pivot pin, a soleholder member rotatably mounted to said swivel member around an axis lying parallel to said vertical pivot pin, said soleholder member being normally held against rotation relative to said swivel member by an antirotation lock, said antirotation lock comprising a locking pin which extends in locked position through a horizontal division between said swivel member and said soleholder member, said soleholder member being unlocked from the locking pin by swinging the swivel member through a predetermined angle out of a central position by relative displacement of the swivel member in opposition to the force of said pivot pin spring.
 2. A toe iron according to claim 1, wherein said antirotation lock comprises two parts, one part being mounted coaxially on said vertical pivot pin and the other part being a socket provided in said soleholder.
 3. A toe iron according to claim 2, wherein the free end portion of said pivot pin defines said one part of said antirotation lock.
 4. A toe iron according to claim 2, wherein said one part of said antirotation lock comprises a plunger slidably held axially in said pivot pin with the free end portion of said plunger protruding from said pivot pin and restoring means biasing said plunger outwardly.
 5. A toe iron according to claim 2, wherein said soleholder defines an oblique cam surface on each side of said socket to guide said one part of said antirotation lock.
 6. A toe iron according to claim 1, including adjusting means for adjusting the force of said spring.
 7. A toe iron according to claim 6, wherein said adjusting means comprises, a nut contained within said swivel member and threadably engaged with said pivot pin.
 8. A toe iron according to claim 7, wherein a stud coacts with said nut and said pivot pin to prevent rotation of said nut relative to said pivot pin.
 9. A toe iron according to claim 8, wherein said swivel member defines a vertical slot through which said stud projects, and a release hardness scale is provided on one side of said slot so that said stud constitutes an indicator of the release hardness.
 10. A toe iron according to claim 22, wherein a pedal is provided on said soleholder to engage the underside of the forward end portion of the skiing boot sole.
 11. A toe iron according to claim 1, wherein runon ramps are fastened to the skis for the swivel member to provide for the relative displacement of said locking pin between said swivel member and said soleholder member. 